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., Woosuk University, Wanju-kun, Chonbuk, Korea 3 Center for Nondestructive Evaluation, Iowa State University, IA, USA 4 Division of Mechanical and Automotive Eng., Kongju University, Konju, Korea 5 School of Mechanical Engineering, Chosun University, Kwangju, Korea a jwpark@chosun.ac.kr, bkhim@core.woosuk.ac.kr, ciyyang@chosun.ac.kr Keywords: Carbon-fiber Reinforced Plastics (CFRP), Fiber Orientation, After and Before Curing, Ply-by-Ply Vector Model, Defect Angle Abstract.
The layup of a CFRP (carbon-fiber reinforced plastics) composite laminates affects the properties of the laminate, including stiffness, strength and thermal behavior.
Another complication arises in determining the values and functions of the orientation of transmitter and receiver and a signal reduction factor to be used in the computation of amplitude for many plies.
The first assumption used is that the interface and beam spreading losses are negligible, that is, all a signal reduction factor terms equal one.

They influence the ease with which fibre-cement is handled at fresh state and can also affect hardened state properties.
The purpose is to modify the fibres surface without affecting their bulk properties and their physical integrity, which is expected from the use of soft experimental conditions that avoid the use of swelling and hydrolysing solvents.
Effects of fiber surface treatments on mechanical properties of wood fiber–cement composites.
Wood fiber surface treatment level effects on selected mechanical properties of wood fiber–cement composites.
Properties of concrete. 4th ed.

Anodizing and plasma electrolytic oxidation (PEO) techniques were used to produce oxide coatings on the Al6061 and Al319 alloys, and the corrosion properties of these coatings in the alternative fuel environments were also evaluated.
This means that the ethanol content has little effect on the corrosion properties of 304 stainless steel.
Previous works reported that the main factor affecting the corrosion rate of a mild steel in the ethanol/water/sulphuric acid system is the conductivity of the medium, and the conductivity increased when the water percentage in the ethanol-water mixture increased [8].
Figs. 5(a) and (b) clearly show the improved corrosion properties of the oxide coatings on both the Al6061 and Al319 alloys in the E85 medium.
In particular, the anodized Al6061 coating exhibits a forward reverse scan back to a lowest current density region, which means superior passive properties.

Introduction Leather contains fibrous proteins such as collagen and elastin, and exhibits special mechanical properties that originate from this unique structure collagen.
Hazardous Materials Vol. 129 (2006), p. 143. ].The preservation of skin is achieve by the tanning process that gives the final product specific properties such as stability, appearance, elasticity and protection against some environmental effects, such as microbial degradation, heat sweat or moisture [[] K.
Dechroming is the treatment given to the chrome shavings in order to maximize the removal of chromium from leather without affecting the properties of the original fibres.
Dechroming The aim of the dechroming process is to remove the chrome from the tannery shavings without affecting the properties of the original fibers.
The main factor that made ​​it possible to achieve the highest rate of dechroming is related to the fact that, in this work, the leather waste was micronized to reduce the particle size, resulting in fibrous particles sizes around to 16 mm.

Fang, Microstructure and mechanical properties of Mg97Zn1Y2 alloy reinforced with LPSO structure produced by semisolid squeeze casting, Materials Science and Engineering: A 732 (2018) 359-367
Zhu, Effects of rheoforming on microstructures and mechanical properties of 7075 wrought aluminum alloy, Transactions of Nonferrous Metals Society of China 20(3) (2010) 355-360
Wang, Effects of Forming Processes on Microstructures and Mechanical Properties of A356 Aluminum Alloy Prepared by Self-inoculation Method, Materials Research 22 (2019)
Song, Microstructure characteristics and mechanical properties of rheocasting 7075 aluminum alloy, China Foundry 10(5) (2013) 277-281
Chen, Effect of Si, Cu and Fe on mechanical properties of cast semi-solid 206 alloy, Transactions of Nonferrous Metals Society of China 20(9) (2010) 1555-1560

Introduction It was the key factor which inducing slope in Three Gorges reservoir area that rainfall and reservoir water level change.
In order to demonstrate the rain type which caused landslide resurrection, select typical thirty seven days rainfall in 1983 to saturated and unsaturated seepage analysis [1-11], and explore the impaction which rainfall pattern affected landslide resurrection, and lay a foundation to further study the rainfall on the impact of the landslide in Three Gorges Reservoir.
Table 1 Physical parameters of Landslide Soil properties E /MPa μ C/kPa φ(°) γ/kN·m-2 Permeability /m·d-1 Natural Saturation Upper landslide 1000 0.35 90 37 24.0 25.0 0.8 Lower landslide 1000 0.35 90 37 24.0 25.0 0.8 Slip band 100 0.35 77 28.4 20.2 22.4 0.0001 Slip bed 20000 0.25 Fig.1.
[9] Qiang Feng, Shirong Xiao, Mechanical Mechanism Analysis for Qianjiangping Landslide Damage on Three Gorges Reservoir, Advanced Materials Research,Vol. 340:126-129,2012

By mechanical analysis way, in the course of drafting the mathematical models of drafting force in back zone and force impressing on sensor are educed; the drafting force is detected on cotton spinning frame utilizing detected equipment of drafting force designed by ourselves.
Introduction Drafting force has a final effect on the change of slow fiber to rapid fiber in drafting zone, so dynamic performance of drafting force has close relations with evenness of output fiber strand, affects the evenness, numbers of neps and thick-thin-place of yarn.
G.A.R.Foste etc.n[4-6] had the main energy concentrating on the exploration of unevenness aspect, but no enough regard about mechanical factor.
When detected concretely, the quality require to spring leaf and strain resistance was higher, and the stability of this device was bad, life of strain gauge was shorter, maintenance harder; Hall effect wattmeter serve as sensor by OLSEN[10], connected directly in micro motor power circuit, to measure dynamic drafting force of sliver, but this was difficult in practical using; in 1979 GRAHAM[1] used linear variable differential transformerr as sensor to research the relations between fiber property and drafting force waving; the analysis instrument of fiber’s drafting force developed by The American Viscose Corporation[3], made a travelling block connected with a tension sensor, then had the sliver round travelling block about 180°.
When the draft multiple of back zone is 1.1-2.0，twist factor of roving is 90，dry weight per unit of roving is 4.35 g/10m，roller center distance of back zone is 53 mm, woven yarn that count is 18.5tex, twist is 77twist/10cm is spun。

Effect of Friction Coefficient on the Stiffness Excitation of Gear Hu Yumei1,2 ,a, Xue Deshuang1,2,b and Pi Yangjun1,2,c 1State key laboratory of mechanical transmission, Chongqing University, Chongqing, China 400044 2Graduate students innovation base of Chongqing University, Chongqing, China 400044 acdrhym@163.com, b xdshuang11@126.com, ccqpp@cqu.edu.cn Keywords: Friction coefficient, Time-variable stiffness, Loads on gear teeth, Stiffness excitation.
Introduction The vibration noise of gear systems which causes from several internal excitations in which stiffness excitation is a major one will affect the performance and reliability of gear system.
Nonlinear dynamic model included friction force is established by Zhu Enyong et al. [4] Multi-degree of freedom straight gear model with friction force and time-variable stiffness is established by Song He et al. [5] to forecast the effect of which on the vibration property of the system.
(2) Different friction coefficients have different effects on gear composite stiffness and gear load which indicate that friction coefficient is a major factor which can affect the stiffness excitation of the gears
While the maximum absolute ratio value of differential value of stiffness variation under different friction coefficients to the stiffness variation amplitude without friction for multiple gear pairs is 22.87% due to the existence of other excitation factors.

Vibration Simulation of Roll Grinder Measuring Device Based on ADAMS/Vibration Liu Jing1,a, Li Hao-lin1,b 1 Mechanical engineering college, University of Shanghai for Science and Technology, Shanghai, China, 200093; a liujing-xd@tom.com , bhaolin@public2.sta.net.cn Keywords: roll grinder; measuring device; ADAMS/Vibration; vibration simulation Abstract.
The feed and compensation rates are adjusted according to the feedback value of the testing device, so the vibration performance of the testing device is an important factor affecting the measuring and grinding accuracy of grinder and it is critical for a successful design to restraint the vibration or increasing the anti-vibration ability of the testing device.
The vibration performance study of the testing device is to avoid system resonate vibration and set the stage for further dynamic analysis and control compensation and it mainly includes computing and measuring the characteristic property of the system including natural frequency, modal shape data and damping ratio, etc..
Although the structure can be optimized by theoretical analysis of the testing device dynamic model, it is hard to build a precise dynamic model for too many uncertain factors and it is also very difficult to launch actual shock excitation test.

The order parameter appears to involve in an integrated form all the variety of the factors affecting the system behavior and so makes it possible to describe that behavior in a unique way.
Having discussed above the factors conditioning a material for the surface alternative of crack initiation, we find it possible to express the (aeff)2 term through a function of those factors as (2) Relationship (2) takes separately into account the contributions RSin of the internal stresses and RS of the residual stresses in the surface layer.
Besides the characteristics discussed above as involved in Eq. 2 an Eq.4, more mechanical factors, such as the ratio between the main stresses (in a complex stress field, i.e., if loaded multiaxially) and cycling asymmetry R, tell on the position of the said transition point.
Gigacycle fatigue in mechanical practice.
The effect of frequency on the gigacycle fatigue properties of a Ti–6Al–4V alloy.